bodyguard vs royal household

bodyguard

noun
  • A person or group of persons, often armed, responsible for protecting an individual. 

verb
  • To act as bodyguard for (someone); figuratively, to protect. 

royal household

noun
  • The immediate family and principal courtiers and servants of a monarch 

How often have the words bodyguard and royal household occurred in a corpus of books? (source: Google Ngram Viewer )